Q. I have property in northwestern Minnesota near Lake Itasca. In late August, when the grass had gone dormant due to lack of moisture, I noticed that the sod was turned over in 6- to 8-inch clumps throughout the two-acre area we maintain. What animals would do such a thing, and why? Our neighbors say they are skunks looking for grubs.

Scott Hruska
Blaine

A. Your neighbor is right, says DNR wildlife educator Jan Welsh. Raccoons and skunks in search of soil insects are the most likely culprits, although squirrels will cause similar divots while excavating or burying nuts.

Q. All animals I know having hoofs also have horns or antlers. Horses have hoofs. Why don't they have horns or antlers?

Richard Huettl
Mendota Heights

A. The answer has to do with how closely they are related. Hoofed mammals with horns or antlers with bone cores—deer, giraffes, sheep, and other ruminants—belong to the order Artiodactyla, or even-toed ungulates. Ruminants have an even number of toes (two or four) on each foot. Horses belong to a different order—Perissodactyla, or odd-toed ungulates. These mammals have an odd number of toes (one or three) on each foot and do not have horns or antlers with bone cores. Other families of Perissodactyla include rhinoceroses (which have hornlike protuberances on their snouts, not bony-cored horns) and tapirs.

Q. As an avid berry picker, I'm puzzled why blueberries can be found in abundance some years, while the next year there's nothing. What happens?

Tom Hartwell
Minneapolis

A. Many factors interact to influence how well blueberries produce in any given year, says DNR botanist Welby Smith. Plants produce best the year after a cool ground fire. If there is little snow during winter some plants may winterkill, reducing yield. Other variables include growing season weather and competition from other plants for light, moisture, and nutrients.

Q. We have a cabin in northwestern Wisconsin. Over the past several winters, bark has been stripped from a few of the maple trees near the base of the tree and in the upper branches. In some cases the damage is so severe that the tree dies the following summer. What is causing this? How can we prevent it in the future?

Mike Ayers
Maplewood

A. DNR forest health specialist Mike Albers says damage at the base of a tree is most likely caused by rabbits. Bark stripped from upper branches is most likely caused by squirrels—especially in late winter or early spring—trying to get to the sugary sap and inner bark. They will sometimes completely strip small maple trees, killing them. If the trees are widely spaced, you could try wrapping sheet metal around the trunks to prevent the squirrels from climbing them. If the trees are close together, the squirrels will leap from tree to tree, so sheet metal won't help.

Q. What is the best way to dispose of unused medications? Some say to flush them down the toilet, but doesn't this eventually put all kinds of hazardous chemicals into the water system?

John Henricksson
Grand Marais

A. Over-the-counter and prescription drugs can harm fish and other wildlife if they get into waterways. The Minnesota Pollution Control Agency recommends the following disposal procedure: 1) Keep medication in its original container, obliterating the patient's name on prescription medications. 2) Make the medication unusable by adding water (to pills or capsules) or salt or a strong powdered spice (to liquids) or by wrapping blister packs in duct tape. 3) Wrap the container in tape or hide it in an empty food container. 4) Discard in your household trash.

Q. I have had pet turtles, both painted and map. Both kinds of turtles shake their hands at each other. Why do they do this?

Chris Milbrandt
Winona

A. This action is part of a mating ritual for these native turtles, according to DNR amphibian and reptile specialist Carol Hall. The male faces a female turtle and strokes her head and neck with his long claws, moving them in a trembling or shaking motion. The female may respond by stroking his outstretched limbs with her front claws.

Q. In the Chippewa National Forest on Minnesota 46 there is an area called the Avenue of Pines. Why were these trees planted, and by whom?

Linda Lieser
Faribault

A. These pines, in the Cutfoot Experimental Forest, were not planted by anyone, according to Chippewa National Forest district silviculturist Audrey Gustafson. Rather, the trees are natural regeneration from a harvest around 1910. Brush is cut along this stretch to encourage growth of seedlings that were planted in 2003.

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